The statistical variability and length effects in the tensile transverse behavior of clear timber

In this work, clear timber specimens of different lengths with a small cross-sectional area were cut in the transverse direction of timber boards and tested under tensile loading. Regularly positioned and randomly positioned specimens were cut from different timber boards. Local deformations in each specimen were measured during the tests and the mechanical behavior of specimens of different lengths was compared. Statistics and size effects concerning the elastic modulus and strength were studied. The transverse tensile behavior was approximately linear. The results show very significant variability in the transverse elastic modulus, as high as 1000% between some specimens. The transverse tensile strength decreases linearly with specimen length increase on logarithmic scales.